Safety of recursive Horn clauses with infinite relations
PODS '87 Proceedings of the sixth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems
Algorithms (2nd ed.)
Reasoning about strings in databases
PODS '94 Proceedings of the thirteenth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems
Sequences, Datalog and transducers
PODS '95 Proceedings of the fourteenth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems
A framework for testing safety and effective computability
Journal of Computer and System Sciences
Regular sequence operations and their use in database queries
Journal of Computer and System Sciences
Reasoning about strings in databases
Journal of Computer and System Sciences
Foundations of Databases: The Logical Level
Foundations of Databases: The Logical Level
PALM - A Pattern Language for Molecular Biology
Proceedings of the 1st International Conference on Intelligent Systems for Molecular Biology
The Case for Enhanced Abstract Data Types
VLDB '97 Proceedings of the 23rd International Conference on Very Large Data Bases
Supporting Lists in a Data Model (A Timely Approach)
VLDB '92 Proceedings of the 18th International Conference on Very Large Data Bases
Introduction to Automata Theory, Languages, and Computation (3rd Edition)
Introduction to Automata Theory, Languages, and Computation (3rd Edition)
Safety, translation and evaluation of alignment calculus
ADBIS'97 Proceedings of the First East-European conference on Advances in Databases and Information systems
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We describe the design and implementation of a declarative database query language for manipulating character strings. The language can be used to create logical predicates expressing structural properties of strings and relations between several strings. The predicates can be used to query strings in databases, and by leaving variables uninstantiated, also to generate new strings not contained in the database. A full working system was implemented as an extension of an object-oriented database management system and its query language. The declarative expressions are evaluated by first performing a compilation transforming them to nondeterministic finite state automata and then by simulating these automata using a depth-first search engine. The system checks the safety of each string-manipulation query in advance to preclude infinite ones. This safety checking provides also a compile-time loop-checking mechanism for the search engine, improving its eficiency.